A casino is a gambling establishment, usually a large building, that offers a wide range of gaming options. Most casinos offer table games such as blackjack and roulette, as well as slot machines and video poker. Some casinos also have poker rooms and other more specialized games. In addition, some casinos have restaurants and bars, and some even host live entertainment events.

Gambling in some form has predated recorded history, with primitive protodice and carved six-sided dice found at archaeological sites. The modern casino, however, is a much more elaborate affair. Some are enormous and extravagant, with a mindblowing variety of gaming choices and luxury amenities. These casinos are often called megacasinos, and many have hotels, non-gambling game rooms, restaurants, swimming pools, spas, and other attractions.

Casinos make money by offering a variety of gambling opportunities, some of which involve skill, but most of which are based on chance and pay out winnings according to mathematical odds. This advantage is known as the house edge, and it allows casinos to earn substantial profits over time. Casinos also collect a percentage of each bet, which is known as the vig or rake. In some games, such as blackjack and video poker, the vig is built into the game rules; in others, it is collected by the casino employees who deal the cards or run the tables.

The largest casinos are in Las Vegas, Nevada and Atlantic City, New Jersey. Several Native American casinos are also growing in size and revenue. The number of casinos in the United States is increasing rapidly, thanks to the growth of online gambling.

Modern casinos employ a significant number of security personnel, both to protect patrons and to prevent criminal activity. Typical security measures include a physical security force and a specialized surveillance department that operates closed circuit television. The surveillance system is a critical component of casino security, as it can quickly spot suspicious or blatant behavior. Casinos are often the target of organized crime, and mobster money has made its way into many of them. In some cases, mobster owners have become personally involved in the management of the casinos they own, and have exerted some degree of influence over the outcomes of particular games.

While the modern casino has its roots in 19th-century Nevada, it really took off when gambling became legalized throughout the United States. The first commercial casinos were designed to be destination resorts, and they quickly attracted large numbers of tourists. As more states legalized gambling, more casinos opened, and the industry began to expand worldwide. The elegant spa town of Baden-Baden, Germany, for example, became a popular casino destination 150 years ago, drawing royalty and aristocracy from across Europe. The casinos in the town are still renowned for their beauty. In more recent times, they have attracted celebrities and high rollers from all over the world.